Re: Why named structs and unions? C11 supports anonymous structs and unions

[Paul Eggert]

Daniel Colascione wrote:

> Now we get all the alignment benefits of alignas, but without the ugly "u.s." 
> stuff.

That assumes C11, though. Currently Emacs assumes only C99. Although Emacs can 
use C11 features when 'configure' determines them to work, I don't offhand see 
how this could be done for this particular feature without contorting the C code 
even more than it's contorted now.

> Instead of XCONS(c)->car, we now write XCONS(c)->u.s.car.

Normally in C code we write XCAR (c) instead of writing either form. The u.s. 
business is intended to be used only within a small set of source-code locations 
that need to know the internal structure of Lisp objects, and most C code 
shouldn't care whether it's '->car' or '->u.s.car'. Admittedly there are more 
occurrences of '->u.s.' than we'd like.